README

THE BASIC R README
(See "FAQ" and "RESOURCES" for more detailed information)
(See "INSTALL" for help on installation)
1. INTRODUCTION
This directory contains the source code tree for R, which is a language
which is not entirely unlike (version 3 of) the S language developed at
AT&T Bell Laboratories by Rick Becker, John Chambers and Allan Wilks.
R is free software distributed under a GNU-style copyleft.
The core of R is an interpreted computer language with a syntax
superficially similar to C, but which is actually a "functional
programming language" with capabilities similar to Scheme. The language
allows branching and looping as well as modular programming using
functions. Most of the user-visible functions in R are written in R,
calling upon a smaller set of internal primitives. It is possible for
the user to interface to procedures written in C or Fortran languages
for efficiency, and also to write additional primitives.
The R distribution contains functionality for a large number of
statistical procedures. Among these are: linear and generalized linear
models, nonlinear regression models, time series analysis, classical
parametric and nonparametric tests, clustering and smoothing. There is
also a large set of functions which provide a flexible graphical
environment for creating various kinds of data presentations.
A package specification allows the production of loadable modules for
specific purposes, and several contributed packages are made available
through the CRAN sites (see RESOURCES).
2. HISTORY
R was initially written by Robert Gentleman and Ross Ihaka of the
Statistics Department of the University of Auckland. In addition, a
large group of individuals has contributed to R by sending code and bug
reports.
Since mid-1997 there has been a core group who can modify the R source
code CVS archive. The group currently consists of
Douglas Bates, John Chambers, Peter Dalgaard, Robert Gentleman,
Kurt Hornik, Ross Ihaka, Friedrich Leisch, Thomas Lumley, Martin
Maechler, Guido Masarotto, Paul Murrell, Brian Ripley, Duncan
Temple Lang and Luke Tierney.
3. PRESENT STATUS
The present version implements most of the functionality in the 1998
book "The New S Language" (the "Blue Book") and many of the
applications. In addition, we have implemented a large part of the
functionality from the 1992 book "Statistical Models in S" (the "White
Book").
All the R functions have been documented in the form of help pages in an
"output independent" form which can be used to create versions for HTML,
LaTeX, text etc. A 700+ page Reference Index (a collection of all the
help pages) can be obtained in a variety of formats. The document "An
Introduction to R" provides a more user-friendly starting point. See
INSTALL for instructions on how to generate these documents.
4. GOALS
Our aim at the start of this project was to demonstrate that it was
possible to produce an S-like environment which did not suffer from the
memory-demands and performance problems which S has. Somewhat later, we
started to turn R into a "real" system, but unfortunately we seem to
have lost a large part of the efficiency advantage in the process, so
one of our short-term goals is to revise the memory management mechanism
and look for other candidates for optimization.
Longer-term goals include to explore new ideas: e.g. virtual objects and
component-based programming, and expanding the scope of existing ones
like formula-based interfaces. Further, we wish to get a handle on a
general approach to graphical user interfaces (preferably with
cross-platform portability), and to develop better 3-D and dynamic
graphics.
Sincerely,
The R Core Team.